Tube expansion tool

ABSTRACT

A hand tool for expanding thin-wall metal tubes such as the inlet and outlet tubes of vehicle heater radiators. A pair of cylindrical shank members are joined together at a generally right angle. The free ends of the shank members are formed with a plurality of tapered flat surfaces terminating in an elongated tip. The surfaces form sharp corners at their junctions extending along the tapered ends, which corners expand a damaged tube when either of the tapered ends is rotated and moved downwardly within a tube having a diameter equal to the inserted shank diameter. The other shank member functions as a handle for rotating the inserted shank member within a tube being expanded.

United States Patent [191 Hinerman Jan.8, 1974 TUBE EXPANSION TOOL [76] Inventor: Ralph Hinerman, 120 Seventh St.,

NE, North Canton, Ohio 44720 [22] Filed: Sept. 20, 1971 [21] Appl. No.: 181,854

[52] US. Cl 72/476, 29/270, 72/370 [51] Int. Cl. B21c 3/16 [58] Field of Search 72/344, 370, 476,

[56] References Cited UNITED STATES PATENTS 2,383,573 8/1945 Tomsek 81/71 2,760,799 8/1956 Smith 287/51 2,346,364 4/1944 Dowe 279/83 2,797,599 6/1957 McGarvie 81/71 2,518,886 8/1950 Halvorsen 81/71 2,656,865 10/1953 Bright 145/75 Primary Examiner-Richard J. Herbst Assistant Examiner-James R. Duzan Att0rney-Frease & Bishop [57] ABSTRACT A hand tool for expanding thin-wall metal tubes such as the inlet and outlet tubes of vehicle heater radiators. A pair of cylindrical shank members are joined together at a generally right angle. The free ends of the shank members are formed with a plurality of tapered flat surfaces terminating in an elongated tip. The surfaces form sharp corners at their junctions extending along the tapered ends, which comers expand a damaged tube when either of the tapered ends is rotated and moved downwardly within a tube having a diameter equal to the inserted shank diameter. The other shank member functions as a handle for rotating the inserted shank member within a tube being expanded.

3 Claims, 10 Drawing Figures TUBE EXPANSION TOOL BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a tool construction and more particularly to a hand tool construction for expanding and straightening. deformed tubes, especially automobile heater radiator inlet and outlet tubes. An end of the tube expansion tool is inserted into a damaged tube and rotated to remove dents and expand the tube to its original shape and diameter.

2. Description of the Prior Art Nearly every automobile and truck manufactured in the United States is equipped with a heater for warming the occupants during cold weather. These heaters generally are hot water heaters in which hot water from the main engine radiator is circulated through a small radiator within the vehicle.

These heaterradiators have water inlet and outlet tubes which extend through the firewall of the vehicle and connect with hot water hoses from the main engine radiator. These tubes are formed of a relatively thin metal and are damaged easily during collisions, during repairs on the vehicle heater, or by accident during repair of the vehicle engine.

Unless the tubes have a uniform diameter and are free of dents and deformation the connecting hoses will not seat properly around the tubes and will leak.

Heretofore it has been a time consuming and tedious job to expand, straighten and remove dents from the tubes which usually was done with a screw driver, punch or other miscellaneous tool, since there was no tool known to me for easily performing such work.

Known types of tools for reshaping deformed tube ends such as described in US. Pat. Nos. 1,783,088 and 1,974,963 are unsatisfactory for vehicle heater radiators since the impact force necessary to drive the straightening plug into the tube would loosen the tube connection with the radiator. Also the work space available when the repair is made on the tube while the radiator is installed is limited and would not readily permit driving retaining rings off the tubes.

Other known tube expanders and straighteners are automatic, power operated equipment which would require removal of the radiator from the vehicle for straightening and which are expensive for most radiator repair shops and service stations to purchase.

Thus, the need has existed for a simple, inexpensive and easy operable tool for expanding, straightening and removing dents from thin wall tubes, such as the inlet and outlet tubes for vehicle heater radiators.

SUMMARY OF THE INVENTION Objectives of the invention include providing a tube expansion tool for expanding, straightening, and removing dents from short sections of tubes, such as the inlet and outlet tubes of vehicle heater radiators; providing a tube expansion tool which is hand operated, enabling heater radiator tubes to be straightened without removing the radiator from the vehicle; providing a tube expansion tool which fits the heater radiator inlet and outlet tubes of most all automobiles produced in the United States and many trucks without the necessity of additional adaptor parts which become lost and misplaced; providing a tube expansion tool in which one portion servesas the tool handle during straightening one size of tube and which portion serves as the straightening member for another size tube; providing a tube expansion tool of simple construction which is sturdy and durable in use, which achieves the stated objectives in a simple, effective and inexpensive manner, and which solves problems and satisfies needs existing in the art.

These objectives and advantages are obtained by the tube expansion tool, the general nature of which may be stated as including a cylindrical shank portion of uniform diameter equal to the internal diameter of a tube to be expanded; the shank portion terminating in first and second ends; handle means attached to the first end for rotating the shank portion and second end; the second end including a plurality of flat surfaces tapered inwardly from the outer surface of the shank portion terminating in a tip; a portion of the tip passing through the axis of the shank portion; a plurality of sharp edges being formed on the second end by the intersection of pairs of the flat surfaces; whereby the edges contact an indented wall portion of a tube, expanding the wall portion outwardly when the second end is rotated within the tube; the handle means including a second shank portion having a uniform diameter different than the diameter of the first shank portion and having a second end similar to the second end of the first shank portion; and a first end of the second shank portion being formed integral with the first end of the first shank portion and the second shank portion extending generally perpendicularly outwards from the first shank portion.

BRIEF DESCRIPTION OF THE DRAWING A preferred embodiment of the invention illustrative of the best mode in which applicant has contemplated applying the principles is set forth in the following description and shown in the drawing and is particularly and distinctly pointed out and set forth in the appended claims.

FIG. 1 is a fragmentary perspective view of a vehicle heater radiator with the improved tube expansion tool shown expanding the radiator water inlet tube;

FIG. 2 is a side elevation of the tube expansion tool;

FIG. 3 is a top plan view of the tube expansion tool;

FIG. 4 is an end elevation of the tube expansion tool shown in FIGS. 2 and 3;

FIG. 5 is a fragmentary end elevation looking in the direction of arrows 5-5, FIG. 2;

FIGS. 6, 7 and 8 are diagrammatic, fragmentary sectional views showing in sequence, the tube expansion tool expanding a deformed tube end such as shown in FIG. 1; and

FIGS. 9 and 10 are fragmentary end elevations similar to FIG. 5, showing two modifications of the tube expansion tool.

Similar numerals refer to similar parts throughout the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT The tube expansion tool is generally indicated at l, and is shown expanding as inlet tube 2 of an automobile heater radiator 3 (FIG. 1).

Radiator 3 is a usual hot water radiator having a plurality of interconnected cells 41 arranged in honeycomblike fashion and connected to water inlet and outlet chambers 5 and 6, respectively. Tubes 2 and 7 are connected to inlet and outlet chambers 5 and 6, respectively, and preferably are provided with annular top flanges 2a and 7a for attachment of flexible water hoses from an automobile eingine radiator.

Tubes 2 and 7 usually are thin-walled, cylindrical tubes formed of brass, and are susceptible to dents and deformations.

The diameters of tubes 2 and 7 have been standardized by the automotive industry to two sizes, one of which is larger than the other, so that radiators 3 installed in most all automobiles and in many trucks produced in the United States have inlet and outlet tubes of either one of the two sizes or a combination of both. Some radiators 3 may have both the inlet and outlet tubes of the larger diameter, or both tubes of the smaller diameter, or a large outlet tube 7 and a small inlet tube 2 as shown in FIG. 1.

Tool 1 preferably is constructed from a single piece of circular steel tool stock and is formed into a right angle having equal length leg members 8 and 9. Members 8 and 9 have cylindrical shank portions 10 and 11, respectively, having uniform diameters equal to the internal diameters of radiator tubes 2 and 7. Thus, shank 10 of member 8 has a diameter equal to the internal diameter of smaller tube 2 and shank 11 of member 9 has a diameter equal to the internal diameter of larger tube 7.

Shanks l0 and 11 terminate in outer ends 12 and 13, respectively, and have inner ends which join at 14 to form a right angle between members 8 and 9.

In accordance with the invention, ends 12 and 13 are formed with a plurality of tapered flat sides or surfaces l5, 16, 17 and 18 which terminate at an elongated chisel-like tip 19. A plurality of sharp corners or edges 20, 21, 22 and 23 are formed by adjacent pairs of sides 15-18, with sides 15 and 16 forming edge 20, sides 16 and 17 forming edge 21, sides 17 and 18 forming edge 22, and sides 18 and 15 forming edge 23.

Sides 15 and 17 preferably are identical to each other and join at right angles with identical sides 16 and 18. The areas of opposite sides 15 and 17 preferably are larger than the areas of opposite sides 16 and 18 so as to form the chisel-like tip 19 having an elongated rectangular shape.

The slopes of opposite sides 15 and 17, and 16 and 18 preferably are equal to each other so that a section taken through ends 12 and 13 perpendicular to their respective axes, indicated at 24 and 25 (FIG. 2), at any position along ends 12 and 13, will form a rectangle centered about the axis such as shown in FIGS. 6 and 7.

The use of tool 1 is diagrammatically illustrated in FIGS. 6, 7 and 8. Tip 19 of shank 10 or 11 which corresponds to the diameter of a particular tube to be expanded and straightened, is inserted into the damaged tube end, for example, tip 19 of shank 10 for tube 2 as shown in FIG. 1.

Members 8 and 9 may be rotated in a clockwise or counterclockwise direction within the tube being expanded. Member 8 is shown rotated in a clockwise direction, (arrow A, FIG. 6) by a repairman by gripping opposite member 9 with his hand 26, shown in dot dash lines, FIG. 1. Member 9 conveniently functions as a handle due to its perpendicular extension outward from member 8.

A downward force also is applied to member 8 through a downward pressure exerted on member 9 by hand 26 as member 8 is being rotated within tube 2.

Edges 23 and 21 of end 12, (FIG. 6) first contact the indented portions of tube 2, indicated at 27. These edges force indented portions 27 outwardly as end 12 is rotated within tube 2. Following edges 22 and 20 next contact any indentations as end 12 continues to rotate and move downwardly within tube 2.

FIG. 7 shows the same cross-section of tube 2 as in FIG. 6 after several rotations of end 12 during which movement, end 12 has moved downwardly into tube 2. As end 12 moves downwardly into tube 2 its rotational diameter increases due to the tapered edges to further expand indentations 27 outward toward the original tube diameter and shape and at the same time draw elongated deformations 28 inwardly.

FIG. 8 shows further the same section of tube 2 as in FIGS. 6 and 7 with end 12 completely inserted into tube 2 after numerous revolutions. Edges 20-23 have removed all indentations and have expanded the walls of tube 2 to the diameter of shank 10.

Rotation of shank 10 within tube 2 further removes any small indentations remaining as well as wrinkles formed in the tube wall by removal of the indentations.

One of the important concepts of new tool 1 is the gradual taper of ends 12 and 13. This taper causes the distance between the center of rotation or axis 24 of end 12 to edges 20-23 to increase as tip 19 and end 12 are forced downwardly into tube 2 as can be seen from a comparison of FIGS. 6, 7 and 8.

Thus, any and all indentation in tube 2 are forced outwardly as end 12 is rotated and moved downwardly into tube 2 due to contact with edges 20-23 and their tapered configuration which increase the diameter of rotation along end 12.

When straightening a badly damaged tube it may be necessary to first pry the top edges 29 of tubes 2 or 7 apart with tip 19 to form an opening large enough for insertion of the tool end. Likewise, tool 1 may be rotated several times or in a reversing rotational motion at any point along the tapered edges, to completely remove all indentations before applying additional downward force moving the tool end further into the tube and further along the tapered edges.

Also to straighten a badly damaged larger tube 7, smaller tool member 8 and end 12 may first be used to remove a portion of the deformations and expand tube 7 partially toward its original diameter before inserting larger member 9 and end 13.

Tool 1 enables a radiator repairman to quickly and easily remove indentations, expand and straighten most all damaged radiator inlet and outlet tubes in heaters installed in automobiles produced in the United States by simply rotating the appropriate size end of a single tool within the radiator tube while applying a downward force. A repair job which heretofore required considerable time or required the replacement of the enitre radiator can be performed in minutes with tool 1.

Tool 1 does not require the user to be an experienced mechanic or repairman but enables anyone possessing a minimum of mechanical skill to properly use tool 1 to repair damaged radiator tubes.

Should the body of the radiator 3 be known to be in satisfactory condition and only tubes 2 or 7 are damaged eliminating removal of the radiator for leakage testing, the expansion of the damaged tube can be made with tool 1 without removing radiator 3 from the vehicle.

Tool 1 has the further advantage of being of solid and rugged construction having no moving parts to adjust or become lost, permitting it to be stored conveniently in a tool box or the like and used repeatedly without the possibility of damage. Tool 1 is illustrated and described as preferably having four flat sides 15-18 and four corresponding corners 20-23 for ends 12 and 13. However, ends 12 and 13 may be formed with a triangular shape, as shown in FIG. 9, having only three flat sides 30 and three edges 31, or formed with five or more flat sides 32 and corners 33, as shown in FIG. 10, without departing from the concept of the invention.

Although the angle of taper of sides 15-118 and corners 20-23, with respect to axes 24 and 25, may be varied without affecting the operation of tool l or without departing from the concept of the invention, it is preferable that the angle of taper be within a range of 5 to to the axis. Preferably, the flat sides and 17 are located at an angle of 10 to the axis, and the flat sides 16 and 18 are located at an angle of 5 to the axis. The greater the angle of taper, the smaller will be the downward movement of the tool end into the tube to increase the expansion diameter of the contacting edges, and vice versa for a smaller angle of taper.

Although tool 1 is described as being intended for use for expanding vehicle heater radiator tubes it also can be used for expanding thin-wall tubes used in numerous other applications by forming shanks 10 and 11 to have the same diameters as the tubes to be expanded.

Accordingly, the tube expansion tool provides a single tool for expanding, straightening and removing indentations from the inlet and outlet tubes of nearly all heater radiators installed in automobiles produced in the United States; provides a tube expansion tool for expanding damaged radiator tubes without requiring removal of the radiator from the vehicle; and provides a tube expansion tool which is effective, safe, inexpensive, simple in construction and durable in use, and which achieves all the enumerated objectives, provides for eliminating difficulties encountered with prior devices, and solves problems and obtains new results in the art.

In the foregoing description, certain terms have been used for brevity, clearness and understanding but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such terms are used for descriptive purposes and are intended to be broadly construed.

Moreover, the description and illustration of the invention is by way of example, and the scope of the invention is not limited to the exact details of the construction shown or described.

Having now described the features, discoveries and principles of the invention, the manner in which the improved tube expansion tool is constructed, assembled and operated,.the characteristics of the new construction, and the advantageous, new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts, and combinations are set forth in the appended claims.

I claim:

1. A tube expansion tool including first and second cylindrical shank portions joined integrally at one end and extending generally perpendicularly outwardly from each other; the shank portions having uniform diameters each of a different diameter equal to the internal diameters of tubes to be expended; the shank portions each terminating in a free end; said free ends each including four flat surfaces tapered inwardly from the outer surface of the shank portion terminating in a tip; a portion of each of said tips passing through the axis of its corresponding shank portion; the angles of taper of opposite flat sides being equal and within a range of 5 to 10 to the axis of the shank portion; adjacent flat surfaces being perpendicular to each other forming sharp edges by the intersection of said surfaces; the edges of one of the first and second shank portions free ends when inserted into a tube having an internal diameter equal to the diameter of the shank portion contacting an indented wall of the tube and expanding the indentation outwardly when the free end is rotated within and moves inwardly into the tube being expanded; and the other shank portion of the tool functioning as a handle for rotating said one inserted shank portion within the tube.

2. The construction defined in claim 1 in which opposite flat surfaces of each shank portion free end are equal in area; and in which two opposite flat surfaces of the free ends of each shank portion are greater in area than the other two opposite flat surfaces of the respective shank portion.

3. The construction defined in claim 1 in which the tip of each shank portion is chisel-like having an elongated rectangular shape. 

1. A tube expansion tool including first and second cylindrical shank portions joined integrally at one end and extending generally perpendicularly outwardly from each other; the shank portions having uniform diameters each of a different diameter equal to the internal diameters of tubes to be expended; the shank portions each terminating in a free end; said free ends each including four flat surfaces tapered inwardly from the outer surface of the shank portion terminating in a tip; a portion of each of said tips passing through the axis of its corresponding shank portion; the angles of taper of opposite flat sides being equal and within a range of 5* to 10* to the axis of the shank portion; adjacent flat surfaces being perpendicular to each other forming sharp edges by the intersection of said surfaces; - the edges of one of the first and second shank portions free ends when inserted into a tube having an internal diameter equal to the diameter of the shank portion contacting an indented wall of the tube and expanding the indentation outwardly when the free end is rotated within and moves inwardly into the tube being expanded; and the other shank portion of the tool functioning as a handle for rotating said one inserted shank portion within the tube.
 2. The construction defined in claim 1 in which opposite flat surfaces of each shank portion free end are equal in area; and in which two opposite flat surfaces of the free ends of each shank portion are greater in area than the other two opposite flat surfaces of the respective shank portion.
 3. The construction defined in claim 1 in which the tip of each shank portion is chisel-like having an elongated rectangular shape. 